Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755466AbbDOORZ (ORCPT ); Wed, 15 Apr 2015 10:17:25 -0400 Received: from e06smtp15.uk.ibm.com ([195.75.94.111]:48159 "EHLO e06smtp15.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754522AbbDOORM (ORCPT ); Wed, 15 Apr 2015 10:17:12 -0400 From: Laurent Dufour To: Andrew Morton , "Kirill A. Shutemov" , Hugh Dickins , Rik van Riel , Mel Gorman , Pavel Emelyanov , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Ingo Molnar , linuxppc-dev@lists.ozlabs.org Cc: cov@codeaurora.org, criu@openvz.org Subject: [PATCH v5 3/3] powerpc/mm: Tracking vDSO remap Date: Wed, 15 Apr 2015 16:16:58 +0200 Message-Id: <29c21a607c8083626e3ce9f4a19cb00b0205dbaa.1429104776.git.ldufour@linux.vnet.ibm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: References: In-Reply-To: References: <20150414123853.a3e61b7fa95b6c634e0fcce0@linux-foundation.org> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15041514-0021-0000-0000-000003960BAC Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2699 Lines: 84 Some processes (CRIU) are moving the vDSO area using the mremap system call. As a consequence the kernel reference to the vDSO base address is no more valid and the signal return frame built once the vDSO has been moved is not pointing to the new sigreturn address. This patch handles vDSO remapping and unmapping. Signed-off-by: Laurent Dufour Reviewed-by: Ingo Molnar --- arch/powerpc/include/asm/mm-arch-hooks.h | 13 +++++++++++++ arch/powerpc/include/asm/mmu_context.h | 23 ++++++++++++++++++++++- 2 files changed, 35 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/mm-arch-hooks.h b/arch/powerpc/include/asm/mm-arch-hooks.h index 63091a19de9f..f2a2da895897 100644 --- a/arch/powerpc/include/asm/mm-arch-hooks.h +++ b/arch/powerpc/include/asm/mm-arch-hooks.h @@ -12,4 +12,17 @@ #ifndef _ASM_POWERPC_MM_ARCH_HOOKS_H #define _ASM_POWERPC_MM_ARCH_HOOKS_H +static inline void arch_remap(struct mm_struct *mm, + unsigned long old_start, unsigned long old_end, + unsigned long new_start, unsigned long new_end) +{ + /* + * mremap() doesn't allow moving multiple vmas so we can limit the + * check to old_start == vdso_base. + */ + if (old_start == mm->context.vdso_base) + mm->context.vdso_base = new_start; +} +#define arch_remap arch_remap + #endif /* _ASM_POWERPC_MM_ARCH_HOOKS_H */ diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h index 73382eba02dc..825cb232eab6 100644 --- a/arch/powerpc/include/asm/mmu_context.h +++ b/arch/powerpc/include/asm/mmu_context.h @@ -8,7 +8,6 @@ #include #include #include -#include #include /* @@ -109,5 +108,27 @@ static inline void enter_lazy_tlb(struct mm_struct *mm, #endif } +static inline void arch_dup_mmap(struct mm_struct *oldmm, + struct mm_struct *mm) +{ +} + +static inline void arch_exit_mmap(struct mm_struct *mm) +{ +} + +static inline void arch_unmap(struct mm_struct *mm, + struct vm_area_struct *vma, + unsigned long start, unsigned long end) +{ + if (start <= mm->context.vdso_base && mm->context.vdso_base < end) + mm->context.vdso_base = 0; +} + +static inline void arch_bprm_mm_init(struct mm_struct *mm, + struct vm_area_struct *vma) +{ +} + #endif /* __KERNEL__ */ #endif /* __ASM_POWERPC_MMU_CONTEXT_H */ -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/